The present apparatus relates to fluid-flow meter and valve control systems that, when operative senses the rate of flow of a fluid, such as water, which is flowing in a distribution network. The control system causes the flow to be shut off by actuating one or more in-line valves. This actuation mechanism, responding to a flow of fluid in excess of a pre-set threshold limit, activates one or more solenoids to isolate a branch of the fluid-carrying system.
The present device particularly relates to low-voltage, electrohydraulic fluid control networks, having pre-set within itself a base profile of flow patterns in the distribution network such that, when this base profile of flow is exceeded, the system will actuate and close the solenoid-controlled valve or valves.
All domestic and commercial structures have nonprocess water distribution systems and these systems have typical variable flow patterns of water usage. These distinct flow patterns occur as a result of water appliance usage, the time-of-day usage as well as as well as the day of the week and/or other variables. For example, it can be established within rather tight upper and lower ranges of water usage, how much water will be used in any given commercial buildings during a specified period of time.
Water fountains, sinks, lavoratories, and water closets all contribute to the volume of flow of water and the profile of water usage on given days and hours of the day. Such profile data of water usage, both the volume per hour and the characteristics of flow, determine the profile of flow as measured over that duration of time, and can be used to program a control system to monitor such flow and activate the system when either the rate of flow or volume of flow exceeds pre-set parameters.
By first establishing such typical profiles in any given application and setting a time limit to any planned intermittent pattern of usage, it is possible to detect unwanted flow, such as may be occurring from a leaking washing machine, overflowing toilets, a ruptured pipe, or a sprinkling garden hose left on accidentally. In a residential application, for example, it has been established that a typical single-family dwelling would not normally have water flowing continuously for more than thirty minutes, except when watering a lawn or washing an automobile. By incorporating a flow-sensitive switch controller in the incoming water line just after the main shut-off valve, a time-delay relay can start the time cycle each time flow commences.
Should the timed flow-volume of water in the system exceed the maximum set by the timer, the system automatically shuts off by energizing a solenoid valve that is also located in the main line of the distribution system. When this solenoid is energized, the valve closes and the distribution line is shut down.